Visibility was recorded 1000 meters at 5.30 am and it dropped to 600 meters at 8.30 am, the official said.
At the Indira Gandhi International Airport several early morning departures were delayed with visibility going down below 75 metres. At least 10 flights were delayed due to poor visibility.
Foggy conditions also hit train traffic in the national capital region.
According to railway officials, 12 Delhi-bound trains were delayed and 30 were cancelled.
An official of the MeT department has predicted mainly clear skies for the day.
"The sky will be mainly clear. The maximum temperature is expected to hover around 22 degrees Celsius," the official added.
On Sunday, the minimum temperature was recorded at 14.4 degrees Celsius while the maximum temperature had settled at 21.5 degrees Celsius.
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